Revolving eccentric screen



No. 622,035. Pat ented Mar. 28, I899. .1. n. BRAY. REVOLVING EBCENTRIG SCREEN;

(Application filed Mar. 28, 18 98.)

(No Model.)

Fries.

JOSEPH n. BRAY, or CHICAGO, ILLINOIS, ASSIGNOR TO HAMILTON BORDEN,

or SAME PLACE.

REVOLVING ECCENTRIC SCREEN.

SPECIFICATION forming part of Letters Patent No. 622,035, dated March 28, 1899.

Application'filed March 2 :1 8 9 To all whom it may concern.-

Be it known that I, JOSEPH D. BRAY, a eitizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Revolving Eccentric Screen, of which the following is a specification, reference being had to the accolnpanyin g drawings, which form' a part hereof.

My invention relates to screens for separating a mixed mass of material of varying-sized pieces into piles of approximately the samesized pieces, the piles being graded according to the size of the pieces of material in them, and it relates particularly to means for agitating the materials as they pass over the screen, so they will be more readily separated into the desired classes.

In the drawings, Figure l is a partial plan, and Fig. 2 a side view, of myimproved screen. Fig. 3 is a detail View showing the notched disks and the method of attaching them to the shaft.

Similar figures indicate similar throughout the several views.

Mounted in frames 11 on each side of the screen (only one shown in Fig. l) are a series of shafts 12 to 19, inclusive, having mounted upon them a series of large serrated disks 20, with smaller corrugated disks 21 between them. and the disks have angular points 23, adapted to fit in them and hold the disks in place.

On shafts 12 and 13 there is one small disk 21 between two large ones 20. On shafts 14C and 15 there are two, .on shafts 16 and 17 three, and on shafts 18 and 19' four small disks between each pair ofv large disks 20. The result of this spacing is that, as shown in the drawings, the openings between 12 and 13 are small, and the spaces between the disks on each successive pair of shafts is a little larger than the last until shafts 18 and 19 are reached, where the spaces are very large.

One very important feature of my invention is that I mount the disks eccentrically upon the shafts, so that as they revolve they stir up the materials upon the screen and assist in causing them to travel along the screen.

parts through chute 30.

The shafts have notches 22 in them,

$eria1No. 676,380. (No model.)

At the ends of shafts 12 to 19, inclusive, are bevel-gears 24, meshing with other bevelgears 25, mounted upon the shaft 26. Power is applied to this shaft 26 through bevel-gears 2'7 and 28 and shaft 29 or by other suitable means. 30 is the chute through which the coal or other material to be sifted the screen.

The whole screen is placed at an angle, as shown on Fig. 2, so as to assist the travel of the material over it.

The operation of my machine is as follows: The machine is started and coal or other ma terials to be sifted are fed onto the screen I The fine coal passes through between the disks on shafts 12 and 13 into a suitable receptacle placed below. The larger pieces are carried on by the rotating eccentric disks and the incline of the screen, and the next larger pieces pass between 13 and 14. into a suitable receptacle, and so the coal is carried on down the screen. Those pieces which are too large to pass between 18 and 19 pass off the machine into a final receptacle.

By serrating the edges of the disks the disks have more of a grip upon the materials passis fed upon ing over the screen, and thus more easily move them along. I also secure an additional advantage by securing the small disks 21 to the shaft, so that they tend to lift out any pieces which may have lodged between the large disks. In machines previously constructed these small disks have generally been made loose on the shaft and smooth on their outer edges, with the result that lumps of coal or other material would lodge between them, thus filling up the opening and choking the screen, while with thesmall disks serrated and fastened to the shaft they assist in stirring up the material almost as much as the large disks do. The removal of such wedged-in pieces is very, materially assisted by the fact that I make the fit at the notch 22 and angle 23 a loose one, so that the disks have a slight movement or play which tends to dislodge any pieces of material which may stick between two disks.

The word eccentric as used in this specification has the usual dictionary meaning and indicatesasubstantially circular disk mounted on an eccentric axis.

Having thus described my invention, What I claim as new, and desire to secure by Letters Patent, is

1'. A screen consisting of a plurality of rotatable shafts and eccentric disks, having serrated outer edges, secured to each shaft, said disks being so arranged that there are spaces between them for the passage of sifted material.

2. In a screen the combination of a plurality of rotatable shafts geared together to rotate in the same direction at the same speed, and eccentric disks attached to each shaft, said disks being so arranged that there are spaces between them for the passage of the sifted material, the size of the sifting-spaces between the disks on each successive pair of shafts increasing in size, from one end of the screen to the other.

3. In a screen, the combination of a plurality of rotatable shafts geared together to rotate in the same direction at the same speed, and eccentric disks having serrated outer edges and being so arranged upon the shaft that there are spaces between them for the passage of sifted material, the size of the sifting-spaces between the disks on each successive pair of shafts increasing in size from one end of the screen to the other.

4-. In a screen the combination of a plurality of rotatable shafts and a plurality of large disks with small disks between them mounted eccentrically upon each shaft, substantially as described.

5. In a screen, the combination of a plurality of rotatable shafts and a plurality of large disks with small disks between them mounted eccentrically upon each shaft, said large and small disks having serrated outer edges, substantially as described.

. G. In a screen the combination of a plurality of rotatable shafts and a'plurality of large eccentric disks with small eccentric disks between them mounted on each shaft, said shafts being so arranged that there are spaces, between the disks on opposite shafts, for the passage of sifted material.

7. In a screen the combination of a plurality of rotatable shafts, a plurality of large disks with small disks between them mounted eccentrically upon each shaft and means for applying power to said shafts whereby said shafts and disks-are rotated in the same direction.

8. In a screen, the combination of a plurality of rotatable shafts, a plurality of large disks with small disks between them mounted eccentrically upon each shaft, said large and small disks having serrated outer edges, and means for applying power to said shafts whereby said shafts and disks are rotated in the same direction. 7

JOSEPH D. BRAY.

Witnesses:

DWIGHT B. CHEEVER, CHARLES L. HINE. 

